Swivel-type clips are becoming prevalent for securing personal articles, such as cellular phones, pagers, etc., to the belt of a user. In addition to providing the user with the convenience of not having to carry the article in their hand, purse, etc., the swivel-type clip offers the advantage of allowing the article the freedom to rotate about the clip. Rotation of the article aids in preventing the article from jabbing or sticking uncomfortably into the side of the user. This advantage is especially appreciated when the article being secured is a cellular phone generally having a long slender profile.
In contrast to a belt clip, which is attached to the personal article and removed from the belt along with the personal article, the swivel-type clip is intended to remain secured to the belt of the user. The personal article is attached to, and removed from, the swivel clip. It is generally desired that the interface between the swivel clip and the personal article provide for easy, quick removal.
A typical interface includes an undercut feature in the swivel clip that mates to a feature attached to the personal article. Generally, a slot with undercuts at the sides interfacing with an attachment feature, such as a stud with flanges, provides such an interface. Generally, the stud (and subsequently the personal article) is held within the slot by either (a) a positive locking feature, (b) a passive locking feature, or (c) by the geometry of the stud and slot. As used herein, a passive lock is defined as a lock where the feature being used to secure the article in place is designed to be overcome by supplying sufficient force. Overcoming the force is the only way to disengage the mating condition.
A problem with positive locking features is that they generally require a button, latch, or the like, manually engageable by a user to disengage a post or undercut to allow the article to be removed from the clip. Wear of the moving parts (button, latch, etc.) is a concern since cycles in the 10,000+ range can be expected for the normal life of the product. Also, due to the size limitations for the clip-type products (they are generally desired to be as small as possible), reliability is often an issue. The loads that the clips are subjected to can be surprisingly high. For instance, consider the case where a user attempts to sit in a chair and the article gets caught on the chair arm rest. A 200 lb. user can exert a large amount of force generally far greater than the force capable of being handled by the small latching mechanisms. Finally, moving parts typically means that more parts are required for assembly, which relates directly to the manufacturing cost of the clip.
Geometric locking features are generally not burdened with the limitations of wear, reliability and manufacturing costs associated with positive locking features requiring moving parts. However, geometric locking features do create increased difficulty in easily and/or quickly attaching or removing the article from the clip. The theory behind the geometric locking feature is that in one orientation of the article relative to the clip, the article is permitted to move within or relative to the clip, while in a different orientation, the article and clip are locked together or there is sufficient interference to prevent the article from moving with respect to the clip. Thus, depending on the design of the geometric locking feature, the user must generally rotate the article (90.degree., 180.degree., etc.) prior to sliding the article out of the clip, or prior to attaching the article to the clip. The required motion may be considered cumbersome and awkward, especially since preventing the article from accidentally disengaging from the clip requires that the geometric locking feature be such that normal use will not allow the article to detach from the clip.
A problem associated with passive locking features is that, if the passive locking feature is designed with a high enough retaining force to prevent the article from releasing under normal usage, the high force typically makes it difficult for the user to release the article when desired. Conversely, if the force is low enough to allow usability, then it is subject to releasing unexpectedly under normal conditions, thus increasing the chance of the secured article being lost and/or stolen.
Further, a problem related primarily to the positive locking and geometric locking features is that the large size of the securing structure (i.e., moving parts, geometrically shaped parts, etc.) reduces the size of the primary spring utilized to attach the clip to the user's belt, resulting in a spring that is easily deformable and subject to being easily disengaged from the belt of the user.
The present invention is directed toward overcoming one or more of the above-mentioned problems.